#!/usr/bin/env node

const { Readable } = require('stream')

class MyReadable extends Readable {
    constructor() {
        super()
    }
    
    _read() {
        this.push(String.fromCharCode(this.#c++))
        if (this.#c>'z'.charCodeAt(0)) this.push(null)
    }

    #c = 'a'.charCodeAt(0)
}

const rs = new MyReadable()
rs.pipe(process.stdout)
